Shift work responsible for ‘dementia-like’ brain damage – report

Working in shift patterns has a damaging effect on the cognitive ability of workers, a study has shown.

The latest study by the Institute of Occupational and
Environmental Medicine has shown that erratic working patterns
lead to significantly reduced brain function, with a decade of
antisocial shift work prematurely aging the brain by over six
years.

Shift working has already been proven to be responsible for poor
physical health, contributing to conditions such as
cardiovascular disease, breast cancer and ulcers.

The team from the universities of Swansea and Toulouse studied
3,200 employed and retired workers over a period of 10 years.

Speaking to the BBC, Dr Philip Tucker, a member of the Swansea
research team, said there was a “substantial” decrease in brain
function.

He added: “It is likely that when [people on shifts are]
trying to undertake complex cognitive tasks, they might make more
mistakes and slip-ups, maybe one in 100 makes a mistake with a
very large consequence, but it's hard to say how big a difference
it would make in day-to-day life.”

Some of the greatest environmental catastrophes in history were
caused by mistakes made on night shifts.

The Chernobyl disaster in 1986, which saw a reactor at the
Soviet-era nuclear plant go into meltdown, caused a radioactive
fire and the deaths of thousands of people from radiation-related
illnesses. The disaster, which is one of only two events to be
classified a Category 7 on the International Nuclear Event Scale,
was caused by a mistake during a night shift.

Other catastrophes which occurred during night shifts include the
Exxon Valdez oil spill in 1989, in which 750,000 barrels of oil
were spilt off the coast of Alaska, and the Bhopal disaster,
which exposed over 500,000 people to toxic gas, killing tens of
thousands.

Dr Tucker, however, acknowledged that night shifts were a
“necessary evil” that workplaces could not do without,
but that he personally would not work shifts “if I could
possibly help it.”

He believes that medical check-ups for those working antisocial
shifts “should include cognitive performance tests to look
for danger signs.”

The study, published in the British Medical Journal (BMJ), hopes
the new findings will contribute to ongoing research into
dementia. The disease disrupts sleeping patterns in a similar
manner to shift work.

They further discovered that it takes over five years for a brain
to return to regular function after working antisocial hours, a
discovery they hope will lead to beneficial medical advances.

Dr Michael Hastings, from the UK Medical Research Council's
Laboratory of Molecular Biology, told the BBC that the
reversibility of damage from shift work was “really
exciting.”

He added: “No-one else has shown it and no matter how
compromised a person may be there's always hope of
recovery.”

Dementia affects memory, speech and problem solving, and is
usually found in the elderly. Dr Hastings said that the effects
of dementia can be ameliorated by maintaining a steady sleep-wake
cycle.